The invention is generally related to data centers, and more particularly to operation of virtual servers on host devices to provide services supported by data storage subsystems.
Enterprises utilize data centers to provide various services over a network. A data center typically includes groups of host devices and data storage subsystems. Each data storage subsystem includes at least one enterprise storage array having multiple physical storage devices. Technologies such as RAID and remote site mirroring may be used to help avoid data loss. Further, different types of storage devices and tiered levels of storage may be utilized in order to help provide both high performance and high capacity at a practical cost. Client applications and devices communicate with the host devices, and the host devices utilize the storage array in order to provide services to the client applications and devices.
The host devices are typically types of physical servers. Each host device may be dedicated to running a particular application. However it is becoming more common for host devices to implement multiple virtualized servers (a.k.a. virtual machines or VMs) which run applications to provide services to the clients. In particular, the virtual machines on the host may run instances of the same applications or instances of different applications. Having one physical server running multiple virtual machines helps to improve efficiency and reduce total cost of ownership. The virtual machines may be run from a cluster of hosts in order to enhance availability. In response to the failure of a host in the cluster, the virtual machines associated with the failed host can failover (restart) on another host in the cluster.